Draw roll mechanism for hot stretching of artificial filaments



Feb. 13, 1951 R. J. BIRKENHAUER 2,541,149

DRAW ROLL MECHANISM FOR HOT STRETCHING 0F ARTIFICIAL FILAMENTS Filed Aug. 29, 1945 HOT m RETURNJ cow WATER mu Robwd Jasaphfijlzkelzlzaau lm Ew l BY d/zfz/gzL ATTORNEY Patented F eb. 13, 1951 OFFICE nnaw non. MECHANISM roa no'r sram cnmc or ARTIFICIAL ma- Bobcrt J. Birkenhaner, Richmond. Va assignor to E. I. du Pont de Nemours & Company, Wil-' mington, Del, a corporation of Delaware Application August :9. 1945, Serial No. 613,286 Claims. (o1. 20-595) This invention relates to the manufacture of artificial, cellulosic filaments, yarns and threads,

and more particularly to a filament, yarn or thread guiding and stretching mechanism provided with means for applying liquid treating agents to the filament. yarn or thread thereon.

In the spinning of yarn filaments from viscose increased tensile strength can be obtained by suitably stretching the freshly formed filaments, for example, by passing the filaments over at least two positively driven wheels having different circumferential speeds. It is also of advantage to treat the filaments either immediately prior to or during the stretching operation with a liquid (hereinafter termed hot-dip"), e. g. water, or an aqueous solution of an inorganic salt and/or acid such as sodium or ammonium sulfate and/or sulfuric acid or an aqueous solution of an organic material such as glycerol or glycol, maintained at an elevated temperature. And, finally, where the stretched filaments are to be collected in a. centrifugal bucket more rapid shrinkage of the yarn between the feed wheel and the bucket and hence improved cake formation at accelerated traverse frequencies is secured if the hot-stretched filaments are treated with hot or cold water or hot dilute bath prior to collection.

An object of this invention is to provide a simple compact mechanism for stretching artificial filaments, yarns or threads, and for treating the imstretched filaments with hot liquid treating agents and the stretched filaments with cold water.

A further object is to provide concentrically mounted stretching wheels, one of which is associated with means for app hot liquids alone and the other associated with means for treating the yarn with cold water.

A still further object is to provide concentrically mounted stretching wheels having liquid applying means and means to maintain the liquid applied to one wheel separate from the liquid applied to the other wheel.

These and other objects will more clearly appear from the following description and accom- Da y drawing wherein:

Fig. 1 illustrates a viscose spinning and bucket collecting set-up embodying the yarn stretching and liquid treating of my invention.

Fig. 2 is a view, partly in section, illustrating stretching wheels embodying liquid control and associated disposal means constructed in accordance with the principles of my invention.

Referring to the drawing in which like reference numerals and letters designate like parts, reference numeral I indicates a wheel comprised of a generally solid side wall la and an overhanging rim Ib which wheel except for details of construction to be hereinafter emphasized is of the usual type found on bucket spinning machines and constitutes one part of the yarn guiding and stretching mechanism of my invention. Wheel I is fixedly mounted on a hollow shaft 2 which in turn is mounted for rotation on bearings 3 and 4 and is positively driven through gears 5 and 6 by conventional means (not shown). The overhanging rim, the outer surface of which provides the yarn contacting surface of wheel I, is tapered inwardly of the wheel from back to front and is provided near its end of greater diameter with flanges 'I and 22. A second tapered wheel 8 of smaller diameter than wheel I, is mounted at the front and partly within the hollow of wheel I defined by the side wall of the wheel and the overhanging portion of the tapered rim and is afflxed to shaft ll disposed concentrically of and extending through hollow shaft 2; shaft 9 is driven independently of shaft 2 through gears II and II by any suitable means (not shown). Wheel 8 is preferably provided with a flan e I! on its end of greatest diameter which lies within the hollow front portion of wheel I. Treating fluids are continuously supplied to the yarn contacting surfaces of wheels I and 8 by pipes If and I 4 respectively, or their equivalent.

An important feature of my invention is the provision of means for preventing the cold water supplied to the smaller wheel from cooling and/ or diluting the hot dip liquid supplied to the larger wheel, and for separately collecting the fluid thrown from each wheel. These means comprise a plurality of ducts or drain holes I8 which extend through the side wall of wheel I from a point at the front of said wall adjacent the flange I 2 of wheel 8 to the back of wheel I on a line substantially parallel with the taper of wheel I. said holes being further disposed in a circle at the juncture of the side wall and rim of wheel I surrounding the circumference of flange I2, and a shroud I encasing the back and flange of wheel I. Shroud I5 is provided interiorly with a forwardly located circular groove or channel It disposed to receive the fluid treating agent thrown from flange I by centrifugal force and to conduct the same to an opening I9 from which it is taken to a storage receptacle (not shown) or immediately recycled for the treatment of more yarn. A second circular channel I! is located at the back of the shroud where it serves to-collect cold water thrown from the back of wheel I, and to convey the same to an outlet for ultimate disposal.

Disposed to one side of the assembly just described, and mounted on the machine frame (not shown), is a conventional, freely rotatable, yarn guide roller 2|.

In operation, yarn A issuing from spinning bath S is drawn over wheel I at which point it is subjected to the action of a suitable heated treating fluid. From wheel I, the treated yarn is passed around roller 2| and over wheel 8 where it is subjected to the action of cold water supplied to the rim or yarn contacting surface of the wheel, and is then collected in the usual manner in bucket B. The surface speeds of wheels I and 8 are so adjusted that the desired stretch is applied to the yarn between these wheels. By reason of the taper on wheel 8 the excess cold water supplied thereto travels, under the compulsion of centrifugal force, up the slope of the yarn contacting surface and onto the flange from which point it is thrown onto the dished-out front side wall of wheel I. The normal tendency of the water thrown onto wheel I would be to travel up the side of said wheel and thence, in part at least, onto the yarn contacting surface where it would serve to'cool and/or dilute the heated treating fluid thereon. However, by reason of the taper on the under surface of the overhanging flange and of the drain holes formed in wheel I, the water accumulates at the juncture of the flange and side wall and thence escapes to the back of the wheel from where it is thrown (from flange 22) into channel H for recovery. In like fashion heated treating fluid on wheel I travels up the slope of the yarn contacting surface and onto the flange I from where it is thrown into channel I6 for separate recovery.

In the above description my invention has been described with specific reference to the stretch spinning of viscose rayon yarn on a bucket machine. It is obvious, however, that it may be applied to a bobbin machine, used in the manufacture of regenerated cellulose yarn by the cuprammonium process, cellulose acetate yarn, cellulose ether yarn, etc., or in fact in any setup where it is desired to stretch artificial yarns while treating the same successively with several different liquid treating agents.

Mechansim constructed in accordance with the principles of my invention provides a compact arrangement which is simple to startand maintain in operation and, even though the structure is extremely compact, yet it permits easy and convenient application of one treating liquid to the yarn as it passes around one wheel and the application of a different treating liquid to the yarn as it passes around the second wheel without an undesirable mixing of the liquids at any point. This mechanism is of especial advantage in the production of high tenacity regenerated cellulose yarn on bucket machines.

.. As many widely difierent embodiments of this,

invention can be made without departing from the spirit and scope thereof, it is understood that the invention is not limited to the exact embodiments herein disclosed except as defined in the appended claims.

I claim:

'1. In a machine for producing high tenacity yarn by the stretch technique, the improvement which comprises 'in combination two positively and independently driven wheels having yarn contacting, overhanging rim surfaces tapered downwardly from back to front, the minimum diameter of one wheel being greater than the maximum diameter of the other, said wheels being concentrically mounted for rotation about a substantially horizontal axis with the back of the smaller wheel facing the front and being within the overhang of the larger wheel, separate means for applying treating liquids to the yarn contacting surface of each wheel, a plurality of drain holes ext nding through said larger wheel from front to back thereof, said drain holes being disposed in a circle adjacent the rim of the larger wheel and beyond the periphery of the smaller wheel whereby treating liquid thrown fromthe smaller wheel onto the front of the larger wheel is drained to the back of said larger wheel, and

means for separately collecting fluid from each wheel.

2. In a machine for producing high tenacity yarn by the stretch technique, the improvement which comprises in combination a positively driven wheel comprising a side wall and a yarn contacting rim surface overhanging the front of the said side wall, said rim being tapered downwardly from back to front and having two upstanding flanges at the rear thereof, a second positively driven wheel having a yarn contacting rim surface tapered downwardly from back to front, said second whe-l being mounted concentrically with, and at least a portion being contained within the space defined by the side wall and overhanging rim of the first wheel, separate means for applying treating liquids to the yarn contacting surface of each wheel, a plurality of drain holes through the side wall of the wheel extending from the front to the back thereof, said drain holes being circularly disposed in a circle adjacent the rim of the first wheel and beyond the periphery of the flange of the second wheel whereby treating liquid thrown from the second wh-el onto the front of the first wheel is drained to the back of 'said first wheel, and means for separately collecting liquid from each wheel.

3. In a machine for producing high tenacity yarn by the stretch technique, the improvement, which comprises in combination a positively driven wheel comprising a side wall and a yarn contacting rim surface overhanging the front of said side wall, said rim being tapered downwardly from back to front and having two upstanding flanges at the rear thereof, a second positively driven wheel having a yarn contacting rim surface tapered downwardly from back to front and having an upstanding flange at the rear thereof, said second wheel being mounted concentrically with, and having its flange only contained within the space defined by the side wall and overhanging rim of the first wheel, separate means for applying treating liquids to the yarn contacting surface of each wheel, a plurality of drain holes through the side wall of the wheel extending from the front to the back thereof, said drain holes being circularly disposed in a circle adjacentthe rim,

of the first wheel and beyond the periphery of the flange of the second wheel whereby treating liquid thrown from the second wheel onto the front of the first wheel is drained to the back of said first wheel and a shroud encasing the flanges and back of said first wheel, said shroud being provided interiorly with channels disposed to separately receive liquid thrown from each of the flanges of said first wheel.

ROBERT J. BIRKENHAUER.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number 6 UNITED STATES PATENTS Name Date Banigan Oct. 23, 1934 Hoeflnghoif May 28, 1935 Hartmann Nov. 5, 1935 Uytenbogaart Sept. 2, 1941 Swank Apr. 20, 1948 Heim Apr. 26, 1949 FOREIGN PATENTS Country Date Germany Apr. 7, 1936 

